A general description of known configurations of bulk material containers is detailed in the Background section of the U.S. Pat. No. 6,932,266. The U.S. Pat. No. 6,932,266 also describes a number of embodiments of improved bulk material container configurations to which the present invention is specifically directed.
Several of the container embodiments described in the U.S. Pat. No. 6,932,266 and shown in FIGS. 1, 8 and 9 of the U.S. Pat. No. 6,932,266 have been renumbered and are illustrated herein as FIGS. 1, 2 and 3 respectively. Referring thereto, a bulk material container 10 generally includes a forming member 12, a locking mechanism 12a, an outer sleeve 14 and optionally an inner liner 16. The forming member 12 is typically constructed of relatively inexpensive lightweight corrugated material that can be operatively configured to define an internal geometric volumetric shape that defines the bulk material storage portion of the container 10. The forming member and locking assembly are collapsible for storage and transport before use and are easily unfolded and shaped to form an operable box-like container configuration as shown in FIG. 1, and also provide structural support for enabling stacking of loaded/filled containers.
The forming member 12 has a plurality of interconnected sidewalls 12b that are configurable to form a closed perimeter of the internal geometric volume. The bottom edges 17 of the sidewalls 12b are designed to be supported on and carried by a pallet. A locking assembly maintains the forming member sidewalls in predetermined fixed position relative to one another when the container is empty. While the locking mechanism can be physically separable from the sidewalls, in the embodiments shown in FIGS. 1-3, the locking assembly comprises lower extension portions 12a of the sidewalls 12b that fold inwardly along the bottom edges 17 of the sidewalls and overlap with one another to form a bottom surface of the container and of the internal geometric volume. At least some of the inwardly folded sidewall extensions 12a have slots generally shown at 18 for cooperatively receiving and interconnecting with edges or other portions of the sidewall extensions that are folded forming a locking assembly of the sidewall extensions. The locking assembly initially maintains the sidewalls in predetermined fixed relationship to one another around the defined internal volume when operatively assembled, and prevents the sidewalls 12b from riding or sliding upward in a direction away from the bottom of the forming member during filling of the container.
As described in the U.S. Pat. No. 6,932,266, an optional bag/liner illustrated at 16 in FIG. 1 may be inserted within the internal geometric volumetric shape of the forming member to accommodate the particular bulk material with which the container will be used. The bag/liner 16 may for example, protect the contents of the container system and/or prevent leakage of liquids or sifting of powders out of the forming member. Such bags/liners are well-known in the art and described in more detail in the U.S. Pat. No. 6,932,266.
The sleeve member 14 is sized to cooperatively and snugly engage and circumferentially surround substantially the entire outer peripheral sidewall portions 12b of the forming member 12. The sleeve 14 is preferably configured in a continuous manner from a flexible, woven fiber material known for its strength and light weight. The sleeve is sized to extend down to and beyond the lower edges 17 of the sidewalls 12b. In the container embodiment illustrated in FIG. 1, the lower portion of the sleeve 14 that extends beyond the lower edges 17 of the sidewalls 12b is folded back up along the sidewalls, as shown at 15, to provide additional strength along the lower portions of the sidewalls.
In the container illustrated in FIGS. 2 and 3, those portions of the sleeve 14 that extend beyond the lower edges 17 of the sidewalls 12b are folded inwardly under the lower edges 17 of the sidewalls 12b and engage the lower surfaces of the sidewall extension portions 12a forming the locking assembly and the bottom of the container. The sidewall extension members interlock with one another by means of the angled slot configurations generally shown at 18. Referring to the container embodiment shown in FIGS. 2 and 3, it can be observed that when the lower extension members 12a are operatively folded to form the container bottom and locking assembly, portions of the extension members 12a horizontally overlap one another forming several vertical gaps or void areas G between overlapping surfaces of the extensions 12a. As the sleeve 14 is folded under the lower edges 17 of the sidewalls 12b, excess sleeve material gathers under the bottom of the container adjacent the corners of the forming member. The excess sleeve material is typically tucked into the gaps or void areas G as illustrated at 19a. As described in the U.S. Pat. No. 6,932,266, tucking the excess sleeve material under the forming member and into the gaps G helps to counteract undesired upward sliding movement of the sleeve 14 along the sidewalls 12b as outward pressure is exerted on the forming member and sleeve as bulk material is loaded into the container. As the weight of bulk material loaded into the container increases, downward pressure exerted by the material on the lower extension members 12a of the forming member vertically compresses the sleeve material in the gaps G between the overlapping extension members 12a, tightly sandwiching and holding the sleeve member therebetween as the pressure increases.
Bulk material container assemblies of the type generally described above have been well received in the market place and have been used by a wide variety of customers for a wide range of different bulk materials. Such diversified use has uncovered aspects of embodiments, configurations and features of the bulk material container assemblies that can be improved upon to enable customized response to customer and content diversity and the market place competitive environment.
One such area for improvement relates to maintaining the overlying sleeve in optimal operative position overlying the forming member during handling and use of the container. In theory, the tucked in sleeve material design described above works well if reasonably careful handling of the container is maintained between its assembly stage and its placement and positioning on a pallet prior to loading the container. However, it has been found that operators assembling the containers are prone to tossing assembled containers onto the pallets and to sliding them across the pallet surfaces when positioning or “squaring-up” the container on the pallet for loading. In doing so, such jarring and sliding movement can cause the previously tucked in lower sleeve material 19a to be jarred or dislodged from and out of its tucked in position in the gaps or void areas G formed between the extension members 12a. Once dislodged from their tucked in positions, the loose sleeve end portions simply rest on the pallet surface and potentially in a manner that protrudes outside of the container's footprint, thereby potentially enabling the sleeve 14 to slide upwardly along the forming member sidewalls 12b during loading of bulk material into the container and during subsequent handling and shipment, potentially decreasing the effectiveness of the sleeve to reinforce the forming member in its intended manner. The present invention addresses this issue.
Another area addressed by the invention relates to a modification of the forming member that facilitates assembly of the container, and in particular of the process of sliding the sleeve into the desired operative position overlying the forming member.